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Journal articles on the topic 'Pulp detachment'

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Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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1

KEMPPAINEN, KALLE, OSSI LAITINEN, MIKA KÖRKKÖ, MIRJA ILLIKAINEN, and JOUKO NIINIMÄKI. "Analysis of prewetting conditions for old magazine papers before pulping in deinking." June 2011 10, no. 6 (July 1, 2011): 7–15. http://dx.doi.org/10.32964/tj10.6.7.

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Recent research on deinking with an old newspaper (ONP)/old magazine (OMG) furnish and with a 100% ONP furnish demonstrates that the ink-substrate bond might not be sufficiently weakened within the short wetting time used in conventional pulping. If enough time for paper wetting is allowed before pulping, better ink detachment could be achieved when compared with conventional pulping. However, it has remained unclear how different prewetting conditions affect ink detachment and fragmentation when processing OMG-based furnish, such as supercalendered (SC) and lightweight coated (LWC) papers. In this study, we investigated the influence of prewetting time, temperature, and chemistry on the optical properties of rotogravure printed SC and heatset offset printed LWC-based pulps, when prewetting is performed without mechanical action before the actual pulping process. Different prewetting times (0-24 h) and temperatures (25°C-65°C) were tested with conventional alkaline soap chemistry and with reduced alkaline soap chemistry. The results for SC pulp support earlier findings and reveal that ink detachment can be improved by wetting SC paper with conventional deinking liquor before pulping. With SC paper, the longer the prewetting time, the lower the amount of attached ink after pulping. Ink that is printed on a coating (LWC paper) is easily detachable; therefore, its release cannot be improved by prewetting. Ink fragmentation was similar with and without prewetting treatment for SC- and LWC-based pulps.
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2

PAOLIELLO, FLAVIO. "Corrosion damage and in-service inspection of retractable sootblower lances in recovery boilers." October 2021 20, no. 10 (November 1, 2021): 655–62. http://dx.doi.org/10.32964/tj20.10.655.

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Several reports of accidents involving serious mechanical failures of sootblower lances in chemical recovery boilers are known in the pulp and paper industry. These accidents mainly consisted of detachment and ejection of the lance tip, or even of the entire lance, to the inside of the furnace, towards the opposite wall. At least one of these cases known to the author resulted in a smelt-water explosion in the boiler. In other events, appreciable damage or near-miss conditions have already been experienced. The risk of catastrophic consequences of the eventual detachment of the lance tip or the complete lance of a recovery boiler soot-blower has caught the attention of manufacturers, who have adjusted their quality procedures, but this risk also needs to be carefully considered by the technical staff at pulp mills and in industry committees. This paper briefly describes the failure mechanisms that prevailed in past accidents, while recommending inspection and quality control policies to be applied in order to prevent further occurrences of these dangerous and costly component failures. Digital radiography, in conjunction with other well known inspection techniques, appears to be an effective means to ensure the integrity of sootblower lances in chemical recovery boilers used in the pulp and paper industry.
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3

Chipili, Chitalu, and Clayton Bhondayi. "The role of the pulp-froth interface on particle detachment and selectivity." Advances in Colloid and Interface Science 287 (January 2021): 102296. http://dx.doi.org/10.1016/j.cis.2020.102296.

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4

Zhang, Songping, Olof Norrl�w, Joanna Wawrzynczyk, and Estera Szwajcer Dey. "Poly(3-Hydroxybutyrate) Biosynthesis in the Biofilm of Alcaligenes eutrophus, Using Glucose Enzymatically Released from Pulp Fiber Sludge." Applied and Environmental Microbiology 70, no. 11 (November 2004): 6776–82. http://dx.doi.org/10.1128/aem.70.11.6776-6782.2004.

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ABSTRACT Glucose, enzymatically released from pulp fiber sludge, was combined with inorganic salts and used as a growth medium for Alcaligenes eutrophus, a gram-negative strain producing poly(3-hydroxybutyrate) (PHB). By controlling the concentrations of the inorganic salts in the growth medium, almost 78% of the cell mass was converted to pure PHB. Efforts were made to find conditions for bacterial growth in the form of a biofilm on a cheap and reusable carrier. A number of positively charged carriers were tested, and the anion exchanger DEAE-Sephadex A-25 was chosen as a microcarrier for packed-bed biofilm cultures of A. eutrophus. Conditions for attachment, growth, and detachment were established. Biofilm formation on the microcarrier is strongly dependent on the ionic strength of the attachment medium. In order to achieve formation of the biofilm and its recovery from the microcarrier, the ionic strengths of the attachment and the detachment media were varied. Low ionic strength was tested for attachment, and high ionic strength was tested for detachment. Although biofilm formation in the packed-bed reactor is limited, the volumetric yield of cells based on the void volume of the packed bed is comparable with the batch culture yield.
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5

GOTO, SHISEI, HIROMICHI TSUJI, ISAO ONODERA, KEIGO WATANABE, and KATSUMASA ONO. "Cavitation-jet deinking: A new technology for deinking of recovered paper." September 2014 13, no. 9 (October 1, 2014): 9–17. http://dx.doi.org/10.32964/tj13.9.9.

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A new method and in-house device for treating secondary fiber were developed. The method is based on the fluid-jet cavitation technique. In this apparatus, pulp suspension was injected into the reacting vessel by using a high-speed jet that produced cavitation bubbles around the jet. The impact of the collapse of cavitation bubbles detached ink, binder, and other contaminants from fiber surfaces. The effects of the cavitating jet (CV-jet) treatment on deinking of the pulp from mixed office waste (MOW) and old newsprint/old magazines (ONP/OMG) mixture were studied. The basic experiments on cavitation control showed that the intensity and region of cavitation were controlled by the jet velocity and the pressure difference in the reacting vessel. The CV-jet generated broad ultrasound waves; the conventional ultrasonic apparatus generated an intrinsic frequency. The MOW test results showed that CV-jet, even without chemicals and high temperature, decreased dirt speckles and reached almost the same dirt reduction level as the mill kneader. Moreover, the CV-jet minimized fiber damage during the process. This yielded pulp handsheets giving much higher paper strength compared with pulp from the kneader. The ONP/OMG test revealed that CV-jet was superior to mill disperser in terms of ink detachment and stickies dispersion.
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6

van Deventer, J. S. J., D. Feng, and A. J. Burger. "Transport phenomena at the pulp–froth interface in a flotation column: II. Detachment." International Journal of Mineral Processing 74, no. 1-4 (November 2004): 217–31. http://dx.doi.org/10.1016/j.minpro.2003.11.002.

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7

GOTO, SHISEI, HIROMICHI TSUJI, ISAO ONODERA, KEIGO WATANABE, and KATSUMASA ONO. "Pilot-scale development of cavitation-jet deinking." September 2014 13, no. 9 (October 1, 2014): 19–25. http://dx.doi.org/10.32964/tj13.9.19.

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A new deinking method for paper recycling using a fluid-jet cavitation technique has been developed. An in-house, laboratory-scale device revealed that cavitation-jet treatment without deinking chemicals decreases ink and dirt content in deinked pulp. As the next step, a pilot-scale deinking device, 10 times larger than the laboratory device, was designed. The specifications of the pilot device were determined by experiments using the laboratory device. The pilot device was installed in a deinked pulp mill, and the effects of multijet nozzles within a reacting vessel, depending on consistencies of the deinked pulp, were investigated. The operation stability of the device was examined as well. The shape and size of an effective cavitation zone for ink detachment were changed by nozzle diameter and upstream pressure of the jet. The results from batch cavitation treatment of deinked pulp revealed that the device could treat the pulp with consistency up to 3.8% by weight and decrease attached ink, dirt specks, and macrostickies without addition of deinking chemicals. Hydrophobic colloidal materials, including microstickies after cavitation treatment, became more difficult to attach to hydrophobic surfaces. Continuous cavitation treatment gave similar results to those from batch treatment. Two types of multiple nozzle arrangements, parallel and cross-nozzle modes, decreased dirt specks to the same level as a mill disperser. On the other hand, the reductions of macrostickies by those modes were higher than with the disperser. Because treatment consistency increased more than 3%, treatment efficiency and device performance were significantly improved. This could be a big step toward practical use of cavitation treatment.
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8

Yuan, Rongcai, Ulrich Hartmond, and Walter J. Kender. "Physiological Factors Affecting Response of Mature `Valencia' Orange Fruit to CMN-Pyrazole. II. Endogenous Concentrations of Indole-3-Acetic Acid, Abscisic Acid, and Ethylene." Journal of the American Society for Horticultural Science 126, no. 4 (July 2001): 420–26. http://dx.doi.org/10.21273/jashs.126.4.420.

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Endogenous concentrations of IAA and ABA in the peel, pulp, seed, and abscission zone of mature `Valencia' oranges [Citrus sinesis (L.) Osbeck] were determined by high-performance liquid chromatography and enzyme-linked immunosorbent assay from early November 1998 to mid-June 1999. Ethylene production of mature `Valencia' oranges during the same period was determined by gas chromatography. IAA concentrations in the pulp and seed were three to five times lower than those in the peel over the 7-month observation period. IAA concentration in the abscission zone and peel was high from late April to mid-May, the period of less responsiveness to abscission chemicals. ABA concentration in the pulp was low over the entire observation period. ABA concentration in the abscission zone and peel was low during the less responsive period. Ethylene production was always low except for a slight increase during late December and early February. The IAA to ABA ratio was high in the fruit abscission zone during the less responsive period. Fruit detachment force of CMN-pyrazole-treated fruit was positively correlated with the ratio of endogenous IAA to ABA or endogenous IAA, but negatively to endogenous ABA in the fruit abscission zone. These data suggest the balance between IAA and ABA in the fruit abscission zone may be an important factor in determining sensitivity and thereby the response of mature `Valencia' orange fruit to abscission chemicals. Chemical names used: abscisic acid (ABA); indole-3-acetic acid (IAA); 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMN-pyrazole).
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9

Kang, Hoyeon, Yongkwon Chae, Koeun Lee, Hyo-seol Lee, Sungchul Choi, and Okhyung Nam. "Long-Term Outcome of Reattached Tooth Fragment in Permanent Anterior Teeth of Children and Adolescents." JOURNAL OF THE KOREAN ACADEMY OF PEDTATRIC DENTISTRY 48, no. 1 (February 28, 2021): 42–49. http://dx.doi.org/10.5933/jkapd.2021.48.1.42.

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This study aimed to evaluate the long-term outcomes of teeth treated with reattachment technique in children and adolescents. Twenty seven permanent anterior teeth from 21 patients treated with fragment reattachment were evaluated. Clinical photos and medical records were used to assess treatment outcomes. Effect of pulp treatment and the ratio of fragment on success rate were statistically analyzed. Detachment of fragment was observed in 17 teeth, and their duration of retention was 21.41 ± 23.39 months. Repeated trauma was found to be the most frequent causes of failure. Pulp treatment before reattachment did not affect the success rate (<i>p</i> > 0.05). The mean ratio of fragment was 0.482 ± 0.147, and the success rate was affected by the ratio of fragment (<i>p</i> = 0.018). The median retention time of the teeth was 72 months if the ratio was under 0.5, and 8 months for that of the others. A significant correlation was found between the ratio of fragment and retention time (<i>p</i> = 0.003). Reattachment can be a predictable treatment option for crown fracture in anterior teeth in children and adolescents when a fracture involves less than 50% of the clinical crown.
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10

HUANG, KAIWU, KRIS STRICKLAND, AARON NOBLE, ROE-HOAN YOON, and CESAR BASILIO. "A new method of studying the fundamental mechanisms involved in pigment liberation from recycle papers." October 2022 21, no. 10 (November 1, 2022): 533–40. http://dx.doi.org/10.32964/tj21.10.533.

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Deinking flotation is the most efficient and widely used method of removing ink particles from printed papers to improve the recyclability. A prerequisite for successful deinking flotation is detachment of pigments from paper fibers, a subprocess known as liberation. The degree of liberation is usually determined via hyperwashing tests, which are costly and time consuming. Furthermore, they provide no information on the fundamental mechanisms controlling liberation. In the present work, we developed a new method in which potentials of the particles in a pulp are measured and analyzed. If pigments are not liberated from paper fibers, a frequency distribution plot gives a single peak, while two peaks appear when they are liberated. One can readily determine the degrees of liberation from the peak positions and peak heights. In addition, the potential data can be used to construct disjoining pressure isotherms using the DLVO theory that are useful to better understand the fundamental mechanisms involved and the roles of different reagents used to improve pigment liberation.
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11

DAS, SUBHASHREE, A. K. DE, P. PERUMAL, A. K. BERA, T. RANA, K. MUNISWAMY, A. KUNDU, et al. "Bioaccumulation and cytological alteration of immune organs of chicken following inorganic arsenic exposure." Indian Journal of Animal Sciences 90, no. 5 (September 10, 2020): 683–87. http://dx.doi.org/10.56093/ijans.v90i5.104604.

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Arsenic is an ecotoxicant that has been found to affect both mammal and avian population. The present study deals with the arsenic deposition in different immune organs of arsenic exposed broiler chicken. Further, its effect on immune cell function and histological alteration was investigated. The study revealed that bursa and liver were the most arsenic deposition prone sites as compared to other immune organs. Histopathological study of the immune organs showed significant structural changes like increased bursal medullary region along with follicular atrophy and detachment of outer serosal layer from the muscularis layer in bursa, decrease in average diameter of white pulp in spleen, decreased cortical as well as medullary region along with less number of Hassall's corpuscle in thymus in the arsenic exposed birds. Arsenic induced apoptosis in peripheral blood mononuclear cells (PBMCs) was also detected and a positive correlation between apoptotic index and dose of arsenic was observed. It may be concluded that insult to avian immune organ by any toxic compound may threaten immune response and may lead to immunosuppression.
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12

Piemjai, Morakot, and Nobuo Nakabayashi. "Direct Tensile Strength and Characteristics of Dentin Restored with All-Ceramic, Resin-Composite, and Cast Metal Prostheses Cemented with Resin Adhesives." BioMed Research International 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/656948.

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A dentin-cement-prosthesis complex restored with either all-porcelain, cured resin-composite, or cast base metal alloy and cemented with either of the different resin cements was trimmed into a mini-dumbbell shape for tensile testing. The fractured surfaces and characterization of the dentin-cement interface of bonded specimens were investigated using a Scanning Electron Microscope. A significantly higher tensile strength of all-porcelain (12.5 ± 2.2 MPa) than that of cast metal (9.2 ± 3.5 MPa) restorations was revealed with cohesive failure in the cement and failure at the prosthesis-cement interface in Super-Bond C&B group. No significant difference in tensile strength was found among the types of restorations using the other three cements with adhesive failure on the dentin side and cohesive failure in the cured resin. SEM micrographs demonstrated the consistent hybridized dentin in Super-Bond C&B specimens that could resist degradation when immersed in hydrochloric acid followed by NaOCl solutions whereas a detached and degraded interfacial layer was found for the other cements. The results suggest that when complete hybridization of resin into dentin occurs tensile strength at the dentin-cement is higher than at the cement-prosthesis interfaces. The impermeable hybridized dentin can protect the underlying dentin and pulp from acid demineralization, even if detachment of the prosthesis has occurred.
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13

Młynarczykowska, Anna, Konrad Oleksik, and Klaudia Tupek-Murowany. "Evaluation of Gas Phase Dispersion in Flotation under Predetermined Hydrodynamic Conditions." E3S Web of Conferences 35 (2018): 01011. http://dx.doi.org/10.1051/e3sconf/20183501011.

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Results of various investigations shows the relationship between the flotation parameters and gas distribution in a flotation cell. The size of gas bubbles is a random variable with a specific distribution. The analysis of this distribution is useful to make mathematical description of the flotation process. The flotation process depends on many variable factors. These are mainly occurrences like collision of single particle with gas bubble, adhesion of particle to the surface of bubble and detachment process. These factors are characterized by randomness. Because of that it is only possible to talk about the probability of occurence of one of these events which directly affects the speed of the process, thus a constant speed of flotation process. Probability of the bubble-particle collision in the flotation chamber with mechanical pulp agitation depends on the surface tension of the solution, air consumption, degree of pul aeration, energy dissipation and average feed particle size. Appropriate identification and description of the parameters of the dispersion of gas bubbles helps to complete the analysis of the flotation process in a specific physicochemical conditions and hydrodynamic for any raw material. The article presents the results of measurements and analysis of the gas phase dispersion by the size distribution of air bubbles in a flotation chamber under fixed hydrodynamic conditions. The tests were carried out in the Laboratory of Instrumental Methods in Department of Environmental Engineering and Mineral Processing, Faculty of Mining and Geoengineerin, AGH Univeristy of Science and Technology in Krakow.
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14

Zhang, Yu, Jian-feng Xiao, He-feng Yang, Yang Jiao, Wei-wei Cao, Huan-min Shi, Jing-fen Cun, Franklin R. Tay, Jie Ping, and Yu-hong Xiao. "N-Acetyl Cysteine as a Novel Polymethyl Methacrylate Resin Component: Protection against Cell Apoptosis and Genotoxicity." Oxidative Medicine and Cellular Longevity 2019 (September 15, 2019): 1–12. http://dx.doi.org/10.1155/2019/1301736.

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The present study investigated the antiapoptotic and antigenotoxic capabilities of N-acetyl cysteine- (NAC-) containing polymethyl methacrylate (PMMA) resin. An in vitro Transwell insert model was used to mimic the clinical provisional restorations placed on vital teeth. Various parameters associated with cell apoptosis and genotoxicity were investigated to obtain a deeper insight into the underlying mechanisms. The exposure of human dental pulp cell (hDPC) cultures to the PMMA resin (Unifast Trad™) resulted in a rapid increase in reactive oxygen species (ROS) level beginning at 1 h, which was followed by time-dependent cell detachment and overt death. The formation of γ-H2AX and cell cycle G1 phase arrest indicated that oxidative DNA damage occurred as a result of the interactions between DNA bases and ROS, beyond the capacities of cellular redox regulation. Such oxidative DNA damage triggers the activation of p53 via the ataxia telangiectasia mutated (ATM) signaling pathway and the induction of intrinsic mitochondrial apoptosis. Oxidative stress, cell apoptosis, and DNA damage induced by the PMMA resin were recovered to almost the level of untreated controls by the incorporation of NAC. The results indicate that the PMMA resin induced the intrinsic mitochondrial apoptosis as a consequence of p53 activation via the ATM pathway in response to oxidative DNA damage. More importantly, the incorporation of NAC as a novel component into the Unifast Trad™ PMMA resin offers protective effects against cell apoptosis and genotoxicity. This procedure represents a beneficial strategy for developing more biocompatible PMMA-based resin materials.
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15

Perone, Nicola. "A technological advance for 21st century obstetricians: the electronically-controlled vacuum extractor." Journal of Perinatal Medicine 46, no. 3 (April 25, 2018): 279–86. http://dx.doi.org/10.1515/jpm-2016-0421.

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Abstract Objective: To describe an innovative electronically-controlled vacuum extractor (VE) in detail and to illustrate its performance characteristics, as observed in a laboratory study. Design: Thirty simulated, vacuum-assisted deliveries. Main outcome measure(s): (1) The ability to measure in real-time of the pull applied and to sound an alert, when the traction approaches the negative pressure under the cup, to prevent its detachment. (2) The recording and printing of a graphic representation of the pull applied (vacuum delivery graph). (3) The emission of a warning signal when the 15-min time limit of continuous cup application on the fetal scalp, is reached. Results: No cup detachment occurred in any of the 15 vacuum-assisted deliveries, in which traction was kept below the adhesive force of the cup [44 lb (20 kg)], except in three cases, due to loss of negative pressure. In the remaining 15 tests, in which traction was greater than the adhesive force of the cup, “pull-offs” inevitably occurred. Furthermore, upon reaching the 15-min time limit of continuous cup application on the fetal cephalic model, a warning signal was emitted, as programmed. Conclusions We demonstrated that the electronically-controlled VE, with its distinctive pull-sensing handle, performs suitably for its intended purposes. The ability of the modernized device to decrease the incidence of cup detachment, secondary to the inadvertent application of excessive traction, may result in considerable safety, medico-legal and didactic advantages.
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16

Papangelo, Antonio. "On the Effect of a Rate-Dependent Work of Adhesion in the Detachment of a Dimpled Surface." Applied Sciences 11, no. 7 (March 31, 2021): 3107. http://dx.doi.org/10.3390/app11073107.

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Patterned surfaces have proven to be a valuable design to enhance adhesion, increasing hysteresis and the detachment stress at pull-off. To obtain high adhesive performance, soft materials are commonly, used, which easily conform to the countersurface, such as soft polymers and elastomers. Such materials are viscoelastic; i.e., they show rate-dependent properties. Here, the detachment of two half spaces is studied, one being flat and the other having a dimple in the limit of short range adhesion and a power law rate-dependent work of adhesion, as observed by several authors. Literature results have suggested that the dimpled surface would show pressure-sensitive adhesion, showing two possible adhered states, one weak, in partial contact, and one strong when full contact is achieved. By accounting for a power law rate-dependent work of adhesion, the “weak state” may be much stronger than it was in the purely elastic case, and hence the interface may be much more tough to separate. We study the pull-off detachment stress of the dimpled surface, showing that it weakly depends on the preload, but it is strongly affected by the dimensionless unloading rate. Finally, possible implications of the presented results in the detachment of soft materials from rough substrates are discussed.
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17

Takenaka, Chiaki, Junji Nakatake, Hidenao Ideta, Kouichi Shinagawa, Ken Watanabe, and Seiji Demizu. "Air Pump for Retinal Detachment With Macular Hole." Ophthalmic Surgery, Lasers and Imaging Retina 25, no. 9 (September 1994): 590–92. http://dx.doi.org/10.3928/1542-8877-19940901-08.

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18

Larvet, Tiphaine, Laetitia Le Pourhiet, and Philippe Agard. "Cimmerian block detachment from Gondwana: A slab pull origin?" Earth and Planetary Science Letters 596 (October 2022): 117790. http://dx.doi.org/10.1016/j.epsl.2022.117790.

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19

Cho, Myung-Rae, and Dong-Chul Han. "Vane tip detachment in a positive displacement vane pump." KSME International Journal 12, no. 5 (September 1998): 881–87. http://dx.doi.org/10.1007/bf02945555.

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20

KIERFELD, JAN, PAVEL KRAIKIVSKI, and REINHARD LIPOWSKY. "FILAMENT ORDERING AND CLUSTERING BY MOLECULAR MOTORS IN MOTILITY ASSAYS." Biophysical Reviews and Letters 01, no. 04 (October 2006): 363–74. http://dx.doi.org/10.1142/s1793048006000318.

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We study the cooperative behavior of cytoskeletal filaments in motility assays, in which immobilized motor proteins bind the filaments to a surface and actively pull them along this surface. Because of the repulsive interaction of filaments, the motor-driven dynamics of filaments leads to a nonequilibrium phase transition which generalizes the isotropicnematic phase transition of the corresponding equilibrium system, the hard-rod fluid. Langevin dynamics simulations and analytical theory show that the motor activity enhances the tendency for nematic ordering. At high detachment forces of motors, we observe the formation of filament clusters because of blocking effects; at low detachment forces, cluster formation can be controlled by the density of inactive motors.
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21

Slater, David M., Michael J. Vogel, Ashley M. Macner, and Paul H. Steen. "Beetle-inspired adhesion by capillary-bridge arrays: pull-off detachment." Journal of Adhesion Science and Technology 28, no. 3-4 (August 13, 2012): 273–89. http://dx.doi.org/10.1080/01694243.2012.705472.

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22

Putignano, Carmine, Luciano Afferrante, Luigi Mangialardi, and Giuseppe Carbone. "Equilibrium states and stability of pre-tensioned adhesive tapes." Beilstein Journal of Nanotechnology 5 (October 7, 2014): 1725–31. http://dx.doi.org/10.3762/bjnano.5.182.

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In the present paper we propose a generalization of the model developed in Afferrante, L.; Carbone, G.; Demelio, G.; Pugno, N. Tribol. Lett. 2013, 52, 439–447 to take into account the effect of the pre-tension in the tape. A detailed analysis of the peeling process shows the existence of two possible detachment regimes: one being stable and the other being unstable, depending on the initial configuration of the tape. In the stability region, as the peeling process advances, the peeling angle reaches a limiting value, which only depends on the geometry, on the elastic modulus of the tape and on the surface energy of adhesion. Vice versa, in the unstable region, depending on the initial conditions of the system, the tape can evolve towards a state of complete detachment or fail before reaching a state of equilibrium with complete adhesion. We find that the presence of pre-tension in the tape does not modify the stability behavior of the system, but significantly affects the pull-off force which can be sustained by the tape before complete detachment. Moreover, above a critical value of the pre-tension, which depends on the surface energy of adhesion, the tape will tend to spontaneously detach from the substrate. In this case, an external force is necessary to avoid spontaneous detachment and make the tape adhering to the substrate.
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23

Marinaro, Gianluca, Emma Frosina, Adolfo Senatore, Kim A. Stelson, and Yuhao Feng. "3D CFD numerical analysis of vane dynamic effects on the pressure ripple in a variable displacement vane pump." E3S Web of Conferences 197 (2020): 07001. http://dx.doi.org/10.1051/e3sconf/202019707001.

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A numerical three-dimensional CFD analysis of a variable displacement vane pump has been conducted, investigating the effects on the pressure ripple caused by the vane detaching from the pressure ring. The volume of the fluid over the vane tip has been re-meshed at every time step as a function of the forces acting on the bottom and the top of each vane. The numerical model has been developed using the commercial tool, Simerics MP+, including turbulence and cavitation models. The validation of the model has been done comparing numerical and experimental data. It has been observed that the detachment of the vane occurs during the transition zones when unwanted pressure spikes are generated by a nonoptimized valve plate design. The prediction of vane detachment is crucial for designing a quieter and more durable pump. Vane collision on the stator ring can be a source of noise producing premature wear of both components. Vane detachment from the stator ring has a large effect on pressure ripple even if the volumetric efficiency is only slightly influenced.
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24

UENO, Hisanori, and Atsushi OKAJIMA. "Detachment of vanes from a cam ring in a vane pump." Transactions of the Japan Society of Mechanical Engineers Series B 52, no. 477 (1986): 2152–57. http://dx.doi.org/10.1299/kikaib.52.2152.

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25

Ellul, M. D., and R. J. Emerson. "A New Pull-Out Test for Tire Cord Adhesion—Part I. Hot Bonding." Rubber Chemistry and Technology 61, no. 2 (May 1, 1988): 293–308. http://dx.doi.org/10.5254/1.3536189.

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Abstract A new pull-out cord adhesion test has been investigated. It consists of a cord partially embedded axially in a long steel-enclosed rubber cylinder. A strain-energy fracture mechanics approach was used to analyze the test in order to derive the energy of detachment, a more fundamental measure of the strength of adhesion than pull-out force, since the modulus and geometry terms are factored out. Good agreement was observed between strain-energy fracture mechanics theory and experiment. In the model system in which steel rods of various diameters were substituted for the cord, rubber thermal shrinkage after cure caused partial internal debonding along the rod if the level of adhesion was not sufficiently high. While no debonding could be detected with truck tire cords, the shrinkage probably reduced any friction effects leading to a more accurate measure of the energy of detachment/fracture. The disadvantage of the Coaxial Shear Pull-out Test geometry (for samples prepared by the hot-bonding procedure as described here) is that scientific discretion based upon measurements of axial stiffness and shear modulus calculations together with subsequent comparisons to shear moduli from an independent measurement, (e.g., hardness) must first be used in order to determine whether debonding has occurred. If debonding is present, then it should be corrected for as shown in the previous discussion section. If no debonding has occurred (e.g., certain brass-plated steel tire cord adhesion systems) then the analysis is more straightforward. Thus, in principle, providing the right analysis is performed on the result, this test is capable of yielding reasonably accurate estimates of the work of adhesion when failure is interfacial or the work of cohesive fracture when failure is in the rubber. In practice however, this pull-out test with samples prepared by the hot-bonding procedure should be reserved for measurements of strong adhesive systems, such as original adhesion of truck tire cords in commercial compounds. A mechanical solution for debonding, involving a cold-bonding procedure is advanced in Part II of this study.
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Tribble, Curt. "Pull Up a Chair, Sit Down, and Listen." Heart Surgery Forum 25, no. 2 (April 15, 2022): E259—E266. http://dx.doi.org/10.1532/hsf.4757.

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When I was a medical student rotating on the various clinical services and thinking about career decisions, a common refrain from those offering advice on these decisions was that an early ‘branch in the career decision tree’ was deciding whether you liked caring for patients or liked doing procedures. I sensed that this advice was creating, or at least suggesting, a false or inaccurate choice. In fact, I even remember hearing that surgeons should not get too close to their patients in order to retain a sense of detachment. Somehow I just didn’t see it that way.
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Heepe, Lars, Alexander E. Kovalev, and Stanislav N. Gorb. "Direct observation of microcavitation in underwater adhesion of mushroom-shaped adhesive microstructure." Beilstein Journal of Nanotechnology 5 (June 25, 2014): 903–9. http://dx.doi.org/10.3762/bjnano.5.103.

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In this work we report on experiments aimed at testing the cavitation hypothesis [Varenberg, M.; Gorb, S. J. R. Soc., Interface 2008, 5, 383–385] proposed to explain the strong underwater adhesion of mushroom-shaped adhesive microstructures (MSAMSs). For this purpose, we measured the pull-off forces of individual MSAMSs by detaching them from a glass substrate under different wetting conditions and simultaneously video recording the detachment behavior at very high temporal resolution (54,000–100,000 fps). Although microcavitation was observed during the detachment of individual MSAMSs, which was a consequence of water inclusions present at the glass–MSAMS contact interface subjected to negative pressure (tension), the pull-off forces were consistently lower, around 50%, of those measured under ambient conditions. This result supports the assumption that the recently observed strong underwater adhesion of MSAMS is due to an air layer between individual MSAMSs [Kizilkan, E.; Heepe, L.; Gorb, S. N. Underwater adhesion of mushroom-shaped adhesive microstructure: An air-entrapment effect. In Biological and biomimetic adhesives: Challenges and opportunities; Santos, R.; Aldred, N.; Gorb, S. N.; Flammang, P., Eds.; The Royal Society of Chemistry: Cambridge, U.K., 2013; pp 65–71] rather than by cavitation. These results obtained due to the high-speed visualisation of the contact behavior at nanoscale-confined interfaces allow for a microscopic understanding of the underwater adhesion of MSAMSs and may aid in further development of artificial adhesive microstructures for applications in predominantly liquid environments.
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Srivastava, Abhishek, and Chung-Yuen Hui. "Large deformation contact mechanics of a pressurized long rectangular membrane. II. Adhesive contact." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, no. 2160 (December 8, 2013): 20130425. http://dx.doi.org/10.1098/rspa.2013.0425.

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In part I of this work, we presented a theory for adhesionless contact of a pressurized neo-Hookean plane-strain membrane to a rigid substrate. Here, we extend our theory to include adhesion using a fracture mechanics approach. This theory is used to study contact hysteresis commonly observed in experiments. Detailed analysis is carried out to highlight the differences between frictionless and no-slip contact. Membrane detachment is found to be strongly dependent on adhesion: for low adhesion, the membrane ‘pinches-off’, whereas for large adhesions, it detaches unstably at finite contact (‘pull-off’). Expressions are derived for the critical adhesion needed for pinch-off to pull-off transition. Above a threshold adhesion, the membrane exhibits bistability, two stable states at zero applied pressure. The condition for bistability for both frictionless and no-slip boundary conditions is obtained explicitly.
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Ackerman, Josef Daniel, C. Ross Ethier, Jan K. Spelt, D. Grant Allen, and Catherine M. Cottrell. "A wall jet to measure the attachment strength of zebra mussels." Canadian Journal of Fisheries and Aquatic Sciences 52, no. 1 (January 1, 1995): 126–35. http://dx.doi.org/10.1139/f95-012.

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A wall jet is presented as a novel means of measuring the attachment strength of zebra mussels. Attachment strength was inferred from a fluid detachment parameter (DP), defined as the nominal wall shear stress at the detachment site × mussel length2. DP varied significantly on natural and artificial substrates: in tests with 288 Dreissena bugensis (≈8–10 mm long), the mean (±SE) DP was 8.9 ± 0.9 mPa∙m2 on limestone/dolomite, 5.6 ± 0.5 mPa∙m2 on polyvinylchloride, 4.3 ± 0.4 mPa∙m2 on stainless steel, 4.2 ± 0.5 mPa∙m2 on aluminum, and 2.5 ± 0.3 mPa∙m2 on polymethylmethacrylate (Plexiglas). The attachment strength of postlarval mussels (plantigrades; <1 mm) was two orders of magnitude less than adult mussels. These results were validated with conventional tensile loadings, in which 633 Dreissena bugensis and 26 Dreissena polymorpha were pulled off substrates with a calibrated force scale. The tensile loadings results were comparable with those of marine bivalves. Good correlation between pull-off force and DP was observed. Information of this nature is useful for the implementation of environmentally benign zebra mussel controls.
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Castillo-Ruiz, Francisco J., Sergio Tombesi, and Daniela Farinelli. "Olive fruit detachment force against pulling and torsional stress." Spanish Journal of Agricultural Research 16, no. 1 (April 26, 2018): e0202. http://dx.doi.org/10.5424/sjar/2018161-12269.

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Olive harvesting often requires high hand labour, considering that workers, with long poles or hand held devices, aid trunk shaker due to low harvesting efficiency. Currently, fruit detachment force (FDF) and fruit fresh weight were used to predict harvesting efficiency, although during harvesting process, fruit is subjected to bending and twisting movement besides pulling forces simulated by FDF measurements. For these reasons, the aim of the present study was to determine FDF evolution under different stalk twisting angles. In order to provide more information about mechanical behaviour of olive stalk, a trial was carried out during ripening process on four olive (Olea europaea L.) cultivars: Frantoio, Arbequina, Leccino and Maurino. FDF under traction force was measured after applying different stalk twisting angles (0°, 90°, 180°, 270°, 360°, 540°, 720º). FDF was considered to be 0 when fruit was detached from the bearing branch during the twisting process. Fruit weight, firmness, ripeness index and oil content were also measured to determine the optimal period for olive harvesting and olive ripening stage at each sampling date. FDF was significantly reduced, usually over 180º, when stalk was rotated before applying the pull force to measure FDF, keeping differences along fruit ripening process. Moreover, stalk twisting was an important variable for olive detachment, considering that fruits detached without pulling forces varied between 10.7 and 58.8% of the total fruits according with the different sampling dates. For these reasons, present and future harvesting systems, should take advantage of stalk susceptibility against torsion or bending strain to increase harvesting efficiency.
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Alsarraf, Jalal, Khaled Alawadhi, Abdulwahab Alnaqi, and S. A. M. Swilem. "A new approach using hybrid power series – cuckoo search optimization algorithm to solve electrostatic pull-in instability and deflection of nano cantilever switches subject to van der waals attractions." International Journal of Engineering & Technology 6, no. 2 (May 2, 2017): 29. http://dx.doi.org/10.14419/ijet.v6i2.7488.

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A hybrid Power Series (PS) and Cuckoo Search via L´evy Flights (CS) optimization algorithm (PS-CS) method is utilized to obtain a solution for the deflection and pull-in instability of a nano cantilever switch in the presence of the van der Waals attractions, electrostatic forces and fringing filed effects. In order to obtain a relation for deflection of the beam, a trial solution including adjustable coefficients, satisfying the boundary conditions of the governing, is proposed. The cuckoo search optimization algorithm is executed to find the ad-justable parameters of the trial solution satisfying the governing equation of the nanobeam. The results are compared with the available results in the literature as well as numerical solution. The results indicate the remarkable accuracy of the present approach. The minimum initial gap and the critical free standing detachment length of the nano actuator that does not stick to the substrate due to the van der Waals attractions, as an important parameter in pull-in instability of the nano switches, is calculated. Utilizing the results of the PS-CS, the stress distribution inside the nano actuator is determined at the onset of the pull-in instability.
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32

Li, Qiang, and Valentin L. Popov. "Adhesive contact of rough brushes." Beilstein Journal of Nanotechnology 9 (September 7, 2018): 2405–12. http://dx.doi.org/10.3762/bjnano.9.225.

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The adhesive contact between a rough brush-like structure and an elastic half-space is numerically simulated using the fast Fourier transform (FFT)-based boundary element method and the mesh-dependent detachment criterion of Pohrt and Popov. The problem is of interest in light of the discussion of the role of contact splitting in the adhesion strength of gecko feet and structured biomimetic materials. For rigid brushes, the contact splitting does not enhance adhesion even if all pillars of the brush are positioned at the same height. Introducing statistical scatter of height leads to a further decrease of the maximum adhesive strength. At the same time, the pull-off force becomes dependent on the previously applied compression force and disappears completely at some critical roughness. For roughness with a subcritical value, the pressure dependence of the pull-off force qualitatively follows the known theory of Fuller and Tabor with moderate modification due to finite size effect of the brush.
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Fazli, Norodin, Ali Koochi, Asieh Sadat Kazemi, and Mohamadreza Abadyan. "Influence of electrostatic force and the van der Waals attraction on the pull-in instability of the CNT-based probe–actuator." Canadian Journal of Physics 92, no. 9 (September 2014): 1047–57. http://dx.doi.org/10.1139/cjp-2013-0202.

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In recent years, carbon nanotubes (CNTs) have attracted great attention in the fabrication of probe tips and actuators for scanning microscopes. Herein, the pull-in instability of CNT-based probe is investigated using a nanoscale continuum model. The Euler–Bernoulli beam theory is applied to model the elastic response of the CNT. The van der Waals attraction is computed from the simplified Lennard-Jones potential. Two analytical methods (i.e., Homotopy perturbation method and Adomian decomposition method) are applied to solve the nonlinear governing equation of the system. Furthermore, the obtained results are validated by comparing with experimental results in the literature as well as numerical solutions of the finite difference method. The pull-in parameters are determined and effect of van der Waals force and a geometrical parameter effect on the instability behavior of the CNT is discussed. Moreover, the detachment length and minimum initial gap of the freestanding CNT probe are determined.
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34

Moser, Christine, Kathrin Maurer, Elisabeth Binder, Dagmar Meraner, Elisabeth Steichen, Daniela Abt, Karin Freund-Unsinn, and Sabine E. Hofer. "Needle detachment in a slim and physically active child with insulin pump treatment." Pediatric Diabetes 17, no. 5 (July 23, 2015): 385–88. http://dx.doi.org/10.1111/pedi.12297.

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35

KOOCHI, ALI, HOSSEIN HOSSEINI-TOUDESHKY, HAMID REZA OVESY, and MOHAMADREZA ABADYAN. "MODELING THE INFLUENCE OF SURFACE EFFECT ON INSTABILITY OF NANO-CANTILEVER IN PRESENCE OF VAN DER WAALS FORCE." International Journal of Structural Stability and Dynamics 13, no. 04 (May 2013): 1250072. http://dx.doi.org/10.1142/s0219455412500721.

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Surface effect often plays a significant role in the pull-in performance of nano-electromechanical systems (NEMS) but limited works have been conducted for taking this effect into account. Herein, the influence of surface effect has been investigated on instability behavior of cantilever nano-actuator in the presence of van der Waals force (vdW). Three different methods, i.e. an analytical modified Adomian decomposition (MAD), Lumped parameter model (LPM) and numerical solution have been applied to solve the governing equation of the system. The results demonstrate that surface effect reduces the pull-in voltage of the system. Moreover, surface energy causes the cantilever nano-actuator with the assigned parameter to deflect as a softer structure. It is found that while surface effect becomes important for low values of the cantilever nano-actuator thickness, vdW attraction is significant for low initial gap values. Surprisingly, the increase in the initial gap, enhances the contribution of surface effect in pull-in instability of the system while reduces the contribution of vdW attraction. Furthermore, the minimum initial gap and the detachment length of the cantilever nano-actuator that does not stick to the substrate due to vdW force and surface effect has been approximated. A good agreement has been observed between the values of instability parameters predicted via these three methods. Whilst compared to the instability voltage predicted by numerical solution, the pull-in voltage obtained by MAD series and LPM method is overestimated and underestimated, respectively.
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36

Ra, H. J., C. Picart, H. Feng, H. L. Sweeney, and D. E. Discher. "Muscle cell peeling from micropatterned collagen: direct probing of focal and molecular properties of matrix adhesion." Journal of Cell Science 112, no. 10 (May 15, 1999): 1425–36. http://dx.doi.org/10.1242/jcs.112.10.1425.

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To quantitatively elucidate attributes of myocyte-matrix adhesion, muscle cells were controllably peeled from narrow strips of collagen-coated glass. Initial growth of primary quail myoblasts on collagen strips was followed by cell alignment, elongation and end-on fusion between neighbors. This geometric influence on differentiation minimized lateral cell contact and cell branching, enabling detailed study of myocyte-matrix adhesion. A micropipette was used to pull back one end of a quasi-cylindrical cell while observing in detail the non-equilibrium detachment process. Peeling velocities fluctuated as focal roughness, microm in scale, was encountered along the detachment front. Nonetheless, mean peeling velocity (microm/second) generally increased with detachment force (nN), consistent with forced disruption of adhesion bonds. Immunofluorescence of beta1-integrins correlated with the focal roughness and appeared to be clustered in axially extended focal contacts. In addition, the peeling forces and rates were found to be moderately well described by a dynamical peeling model for receptor-based adhesion (Dembo, M., Torney, D. C., Saxman, K. and Hammer, D. (1988). Proc. R. Soc. Lond. B 234, 55–83). Estimates were thereby obtained for the spontaneous, molecular off-rate (kooff, (less than or equal to)10/seconds) and the receptor complex stiffness (kappa, approx. 10(−5)-10(−6) N/m) of adherent myocytes. Interestingly, the local stiffness is within the range of flexible proteins of the spectrin superfamily. The overall approach lends itself to elucidating the developing function of other structural and adhesive components of cells, particularly skeletal muscle cells with specialized components, such as the spectrin-homolog dystrophin and its membrane-linked receptor dystroglycan.
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37

Needham, Glen R. "Evaluation of Five Popular Methods for Tick Removal." Pediatrics 75, no. 6 (June 1, 1985): 997–1002. http://dx.doi.org/10.1542/peds.75.6.997.

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Five methods commonly advocated for tick removal from a human or domestic animal were evaluated. The application of petroleum jelly, fingernail polish, 70% isopropyl alcohol, or a hot kitchen match failed to induce detachment of adult American dog ticks (Dermacentor variabilis Say) attached for either 12 to 15 hours or three to four days. Use of forceps or protected fingers enabled satisfactory removal of 29 adult American dog ticks without leaving the mouthparts or attachment cement in the host skin. Four different methods were used to pull lone star ticks [Amblyomma americanum (L)] off the host using forceps (twisting, pulling steadily or jerking straight up, or pulling parallel with the skin). None of the mouthparts broke off, but, contrary to the American dog tick, the cement remained in the skin for all 22 of the Lone Star ticks. It is recommended that the tick be grasped as close to the skin as possible with curved forceps; if these are not available, use tweezers or protected fingers. Pull straight up with steady even pressure. If cement or mouthparts remain, then extract if that is practical. Disinfect bite site before and after tick removal.
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38

SOROUSH, RAHMAN, ALI KOOCHI, ASIEH SADAT KAZEMI, and MOHAMADREZA ABADYAN. "MODELING THE EFFECT OF VAN DER WAALS ATTRACTION ON THE INSTABILITY OF ELECTROSTATIC CANTILEVER AND DOUBLY-SUPPORTED NANO-BEAMS USING MODIFIED ADOMIAN METHOD." International Journal of Structural Stability and Dynamics 12, no. 05 (October 2012): 1250036. http://dx.doi.org/10.1142/s0219455412500368.

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A nano-scale continuum model is applied to investigating the effect of van der Waals (vdW) attraction on pull-in instability of nano-beams in the presence of electrostatic forces. Two cases including the cantilever and doubly-supported beams are considered. The modified Adomian decomposition (MAD) method is employed to solve the nonlinear constitutive equation of nano-beams in the presence of vdW and electrostatic forces for the first time. The results show that the effect of vdW attraction on the instability of the doubly-supported nano-beam is weak when compared to that of the cantilever due to the higher elastic stiffness of the former. Basic design parameters such as the critical deflection and pull-in voltage of the nano-beam are computed. The minimum initial gap and the detachment length of an actuator that does not stick to the substrate due to intermolecular attractions are determined. As a special case, the instability of freestanding nano-electromechanical systems (NEMS) due to vdW attraction is investigated. The MAD solutions are compared with the numerical ones and a proposed lumped model, as well as models available from the literature.
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39

Costalli, Stefano, and Andrea Ruggeri. "Indignation, Ideologies, and Armed Mobilization: Civil War in Italy, 1943–45." International Security 40, no. 2 (October 2015): 119–57. http://dx.doi.org/10.1162/isec_a_00218.

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Ideas shape human behavior in many circumstances, including those involving political violence. Yet they have usually been underplayed in studies of the causes of armed mobilization. Likewise, emotions have been overlooked in most analyses of intrastate conflict. A mixed-methods analysis of Italian resistance during the Fascist regime and the Nazi occupation (1943–45) provides the opportunity to theorize and analyze empirical evidence on the role of indignation and radical ideologies in the process of armed mobilization. These nonmaterial factors play a crucial role in the chain that leads to armed collective action. Indignation is a push factor that moves individuals away from accepting the status quo. Radical ideologies act as pull factors that provide a new set of strategies against the incumbent. More specifically, detachment caused by an emotional event disconnects the individual from acceptance of the current state of social relations, and individuals move away from the status quo. Ideologies communicated by political entrepreneurs help to rationalize the emotional shift and elaborate alternative worldviews (disenchantment), as well as possibilities for action. Finally, a radical ideological framework emphasizes normative values and the conduct of action through the “anchoring” mechanism, which can be understood as a pull factor attracting individuals to a new status.
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40

Kampowski, Tim, Laura Eberhard, Friederike Gallenmüller, Thomas Speck, and Simon Poppinga. "Functional morphology of suction discs and attachment performance of the Mediterranean medicinal leech ( Hirudo verbana Carena)." Journal of The Royal Society Interface 13, no. 117 (April 2016): 20160096. http://dx.doi.org/10.1098/rsif.2016.0096.

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Medicinal leeches use their suction discs for locomotion, adhesion to the host and, in the case of the anterior disc, also for blood ingestion. The biomechanics of their suction-based adhesion systems has been little understood until now. We investigated the functional morphology of the anterior and posterior suckers of Hirudo verbana by using light and scanning electron microscopy. Furthermore, we analysed the adhesion qualitatively and quantitatively by conducting behavioural and mechanical experiments. Our high-speed video analyses provide new insights into the attachment and detachment processes and we present a detailed description of the leech locomotion cycle. Pull-off force measurements of the anterior and posterior suction organs on seven different substrates under both aerial and water-submersed conditions reveal a significant influence of the surrounding medium, the substrate surface roughness and the tested organ on attachment forces and tenacities.
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41

Cross, R. A., I. Crevel, N. J. Carter, M. C. Alonso, K. Hirose, and L. A. Amos. "The conformational cycle of kinesin." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 355, no. 1396 (April 29, 2000): 459–64. http://dx.doi.org/10.1098/rstb.2000.0587.

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The stepping mechanism of kinesin can be thought of as a programme of conformational changes. We briefly review protein chemical, electron microscopic and transient kinetic evidence for conformational changes, and working from this evidence, outline a model for the mechanism. In the model, both kinesin heads initially trap Mg.ADP. Microtubule binding releases ADP from one head only (the trailing head). Subsequent ATP binding and hydrolysis by the trailing head progressively accelerate attachment of the leading head, by positioning it closer to its next site. Once attached, the leading head releases its ADP and exerts a sustained pull on the trailing head. The rate of closure of the molecular gate which traps ADP on the trailing head governs its detachment rate. A speculative but crucial coordinating feature is that this rate is strain sensitive, slowing down under negative strain and accelerating under positive strain.
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42

Woo, Jyh Haur, Hla Myint Htoon, and Donald Tan. "Hybrid Descemet Membrane Endothelial Keratoplasty (H-DMEK): results of a donor insertion pull-through technique using donor stroma as carrier." British Journal of Ophthalmology 104, no. 10 (January 16, 2020): 1358–62. http://dx.doi.org/10.1136/bjophthalmol-2019-314932.

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AimTo evaluate the outcomes and complications of hybrid Descemet membrane endothelial keratoplasty (H-DMEK) using a Descemet stripping automated endothelial keratoplasty (DSAEK) pull-through donor inserter and donor stroma as carrier.MethodsThis was a retrospective interventional case series of eyes with bullous keratopathy (BK) and Fuchs endothelial corneal dystrophy (FECD), which underwent H-DMEK, performed using a bimanual pull-through technique using DSAEK-prepared donor stroma as carrier and the EndoGlide Ultrathin DSAEK donor insertion device. Complex cases with tube shunts, trabeculectomy, aphakia, aniridia, previous vitrectomy, keratoplasty or combined with intraocular lens exchange, were also included. The outcome measures were intraoperative and postoperative complications, best corrected visual acuity (BCVA) and endothelial cell loss after surgery.ResultsOf the 85 eyes from 79 patients, 43.5% (n=37) had BK, 28.2% (n=24) had FECD while 24.7% (n=21) had failed grafts. DMEK was performed in 37 complex eyes (43.5%). Four eyes (4.7%) required rebubbling for graft detachment and two cases of graft failure were observed. A BCVA of 20/25 or better was attained in 44.7% and 57.1% of eyes without pre-existing ocular pathology at 6 and 12 months, respectively. The overall endothelial cell loss was 32.2%±20.5% at 6 months, which improved from 37.2%±20.9% to 24.2%±17.5%, comparing the first 40 and last 45 cases (p=0.012).ConclusionHybrid DMEK offers a controlled ‘pull-through’ technique of donor insertion in the ‘endothelium-in’ configuration, which may be useful especially in complicated eyes. More studies are needed to confirm the long-term endothelial cell loss and graft survival associated with this technique.
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43

Labonte, David, Marie-Yon Struecker, Aleksandra V. Birn-Jeffery, and Walter Federle. "Shear-sensitive adhesion enables size-independent adhesive performance in stick insects." Proceedings of the Royal Society B: Biological Sciences 286, no. 1913 (October 23, 2019): 20191327. http://dx.doi.org/10.1098/rspb.2019.1327.

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The ability to climb with adhesive pads conveys significant advantages and is widespread in the animal kingdom. The physics of adhesion predict that attachment is more challenging for large animals, whereas detachment is harder for small animals, due to the difference in surface-to-volume ratios. Here, we use stick insects to show that this problem is solved at both ends of the scale by linking adhesion to the applied shear force. Adhesive forces of individual insect pads, measured with perpendicular pull-offs, increased approximately in proportion to a linear pad dimension across instars. In sharp contrast, whole-body force measurements suggested area scaling of adhesion. This discrepancy is explained by the presence of shear forces during whole-body measurements, as confirmed in experiments with pads sheared prior to detachment. When we applied shear forces proportional to either pad area or body weight, pad adhesion also scaled approximately with area or mass, respectively, providing a mechanism that can compensate for the size-related loss of adhesive performance predicted by isometry. We demonstrate that the adhesion-enhancing effect of shear forces is linked to pad sliding, which increased the maximum adhesive force per area sustainable by the pads. As shear forces in natural conditions are expected to scale with mass, sliding is more frequent and extensive in large animals, thus ensuring that large animals can attach safely, while small animals can still detach their pads effortlessly. Our results therefore help to explain how nature’s climbers maintain a dynamic attachment performance across seven orders of magnitude in body weight.
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Schubert, Bryan, Jongho Lee, Carmel Majidi, and Ronald S. Fearing. "Sliding-induced adhesion of stiff polymer microfibre arrays. II. Microscale behaviour." Journal of The Royal Society Interface 5, no. 25 (January 22, 2008): 845–53. http://dx.doi.org/10.1098/rsif.2007.1309.

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The adhesive pads of geckos provide control of normal adhesive force by controlling the applied shear force. This frictional adhesion effect is one of the key principles used for rapid detachment in animals running up vertical surfaces. We developed polypropylene microfibre arrays composed of vertical, 0.3 μm radius fibres with elastic modulus of 1 GPa which show this effect for the first time using a stiff polymer. In the absence of shear forces, these fibres show minimal normal adhesion. However, sliding parallel to the substrate with a spherical probe produces a frictional adhesion effect which is not seen in the flat control. A cantilever model for the fibres and the spherical probe indicates a strong dependence on the initial fibre angle. A novel feature of the microfibre arrays is that adhesion improves with use. Repeated shearing of fibres temporarily increases maximum shear and pull-off forces.
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45

Melilli, Dario, Vinícius Felipe Wandscher, Leonardo Ciocca, Giuseppe Currò, Candida Parisi, Giuseppe Gallina, and Paolo Baldissara. "Retention strength of ball-attachment titanium post for removable partial denture or overdenture." Brazilian Journal of Oral Sciences 19 (November 4, 2020): e208798. http://dx.doi.org/10.20396/bjos.v19i0.8658798.

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Aim: To evaluate the retention of an endodontic titanium postwith a spherical head for removable partial denture or overdentureattachment according to surface treatment type. Methods: Sixtyhealthy single-rooted teeth, sectioned at the enamel/cementumjunction, were treated endodontically and steadily fixed in theembedding acrylic resin. The titanium posts were subdivided intofour groups: control, no surface treatment (Ctrl); posts with macroretentivegrooves (MR); air abrasion of the post surface (AB); andposts with macro-retentive grooves and air abrasion of the postsurface (MR+AB). The posts were luted in the root canal usingself-adhesive dual resin cement. Pull-out testing was performedusing a universal testing machine until complete detachment wasachieved. After pull-out testing, the metallic posts were examinedunder an optical microscope and the failures were classifiedbased on the cement distribution pattern on the extracted posts:0, no cement left on the post (cement/post failure); 1, postsurface partially covered by adhered cement (post/cement anddentin/cement mixed failure); 2, post surface completely coveredby cement (dentin/cement failure). The retention data wereanalyzed by one-way ANOVA, Bonferroni–Dunn test (p<0.05)and Weibull analysis. Results: AB showed the highest retentionvalue (485.37±68.36), followed by MR+AB (355.80±118.47), MR(224.63±42.54) and Ctrl (113.12 ± 51.32). AB and MR showedthe highest Weibull moduli. Conclusions: The data indicatedthat air abrasion alone could significantly increase the retentionof titanium posts/attachments for use with overdentures orremovable partial denture.
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NISHIUMI, Takao, Shizurou KONAMI, and Teruyuki MAEDA. "Motion of the Variable Displacement Vane Pump. 2nd Report. Prevention of Vane Detachment by an Additional Chamber." Hydraulics & Pneumatics 24, no. 7 (1993): 828–35. http://dx.doi.org/10.5739/jfps1970.24.828.

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47

Petrungaro, Stefano. "Ethics of work and discipline in transition." Review of Croatian history 15, no. 1 (December 20, 2019): 191–213. http://dx.doi.org/10.22586/review.v15i1.9803.

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The article examines the development of the work discipline and the ethics of work in the shipyard Uljanik in Pula considering the period from the 1980s up to now. Combining oral sources, archival documents, and factory’s magazines, one first conclusion is that in the framework of the self-management system labour discipline was certainly not severe, but neither absent. It was rather in the first half of the 1990s that work discipline vanished, before to be reinstated, in quite new forms, from the second half of the 1990s onwards. Secondly, the article shows how the workers-managers relations worsened in the post-socialist years. This caused a profound emotional detachment by the workers from their work and the factory. In the absence of the older ethics of work, and of a mutual respect between workers and managers (both directors and foremen), what seems to have remained for managing work and the workers is only contemporary labour discipline.
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48

Benedetti, M., D. Bortoluzzi, M. Da Lio, and V. Fontanari. "The Influence of Adhesion and Sub-Newton Pull-Off Forces on the Release of Objects in Outer Space." Journal of Tribology 128, no. 4 (April 26, 2006): 828–40. http://dx.doi.org/10.1115/1.2345407.

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The theoretical background and the numerical modeling results of a ground-based verification activity of a critical space mission phase affected by adhesion issues are presented. Tribological models are first reviewed with an emphasis on the contact forces assessment and their relationship to the geometrical, material, and mechanical properties of the contacting metal bodies. An approach based on a finite element analysis of the contact, accounting for the adhesion forces, is then proposed for studying the contact behavior of smooth surfaces in vacuum. Some solutions aimed at reducing adhesion pull-off forces are discussed. Special emphasis is placed on the role of surface roughness in reducing adhesion. To this purpose, a fractal surface theory is used to estimate interaction forces. The obtained results are applied to discuss the role of adhesion on the release of a test mass under zero gravity as well as to suggest an appropriate detachment procedure that finds a specific application in a scientific space mission.
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49

Jacob, Soosan. "Use of Pressurized Air Infusion For Pre Descemet's Endothelial Keratoplasty (PDEK) - The Air Pump Assisted PDEK Technique." Open Ophthalmology Journal 12, no. 1 (July 23, 2018): 175–80. http://dx.doi.org/10.2174/1874364101812010175.

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Purpose: To assess the advantages offered by the air pump assisted PDEK technique that utilizes pressurized Anterior Chamber (AC) air infusion. Methods: Pressurized air infusion was provided through an anterior chamber maintainer connected to the fluid air exchange system of a posterior vitrectomy machine during surgery. Results: Pressurized air infusion within the AC helped perform Descemetorhexis, prevented bleeding during Peripheral Iridectomy (PI) and synechiolysis, prevented oozing of blood from peripheral corneal neovascularization into the AC and thus helped maintain a non-fibrinous AC environment. In addition, it helped in precise graft manipulation, centration, edge unfolding and unwrinkling after it was floated against the stroma as well as faster graft adhesion. It also prevented AC depth fluctuations during intra-cameral maneuvers and prevented intra-operative as well as post-operative graft detachment. Conclusions: This technique makes several steps of surgery easier and improves graft adhesion.
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50

KAZAMA, Toshiharu, Kohki SASAKI, and Yukihito NARITA. "S1150305 Measurement of Temperature and Vibration of Cam-Ring of Hydraulic Vane Pump : Relationship with Vane Tip Detachment." Proceedings of Mechanical Engineering Congress, Japan 2015 (2015): _S1150305——_S1150305—. http://dx.doi.org/10.1299/jsmemecj.2015._s1150305-.

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